The first thing is floors take a long time to heat and cool, so great for an old peoples home where it wants heating 24/7, but for anyone who either wants it cooler at night, or goes out to work, the slow reaction time is a problem, I fitted an electric version in a wet room, and heat up time of floor was two hours, and to get room warm with a maximum floor temperature of 27°C your looking at setting the floor as back ground heating, radiators do main heating if your not running it 24/7.
But it is reasonably easy to work out, how any heating works, the thermostat opens a valve, and the valve opening turns on boiler, but you need some one way valve so when boiler turns on with one valve opening it does not back feed and cause all the areas to heat together, so a standard two port valve has a micro switch built in to do this.
So thermostat feeds brown and blue on the motorised valve, and the white and orange runs the boiler and main pump.
However you also with most systems need a pump for each UFH set of pipe work, and there is only one micro switch in the two port valve, so we have a relay box which turns one set of micro switch contacts into two sets. One set runs local pump, other set runs main pump and boiler.
So this
bit runs boiler and main pump. And this
bit runs the second pump and connects to thermostats and valves.
So this
goes to the thermostat, line out to thermostat, neutral to thermostat and line in from thermostat. I would guess
has a link in it, as in the main today we use programmable thermostats rather than independent thermostat and timer.
This
and this
needs some reading, I would expect it to supply some thing like this
but it does not make sense for both a two port motorised valve and an actuator to be used, as they basic do the same thing. So I would say only the brown and blue used with the motorised valve, and used instead of actuators.
Or the
feeds a motorised valve for domestic hot water, and the under floor heating uses actuators. It says it feeds a pump for domestic hot water, which seems strange.
But there are clearly more instructions, I am just looking at the instructions you have shown, and it does seem something is lacking, it may work with an oil boiler, but seems rather basic and although could be made to work with a modulating gas boiler it would not work in an efficient way, with gas we have timed on/off valves, but the thermostatic control needs to be analogue either analogue wall thermostats, as with OpenTherm or using thermostatic radiator valves which slowly open or close, they do not switch.
Thermostats like EPH have two controls, it turns the valve on/off, but works as master and slaves to tell boiler what output is required.